You haven't told us what visa stamp you used to enter the US.
Most likely, a trip of less than 30 days will be OK under the visa re-validation rule.
Because your visa is 'tied' the the L-1 primary person ... you'll need proof that he/she is in status.
I suggest you talk to the company's immigration attorney before you travel ... do NOT talk to non-attorneys in HR.
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You can be outside of US in Canada for up to 30 days without a need for a visa.
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Should be fine if less than a 30-day trip and you come back before L-2 status expires. Keep the number of an immigration attorney handy just in case you get issues at the border coming back. Go prepared with proof of L-1 AND L-2 status, including, for the L-1, a letter from employer stating your spouse is still employed there on L-1
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